Signal lamp unit



Sept. 21, i937. s. M. DOVER SIGNAL LAMP UNIT Filed March 7, 1936 INVENTOR. Eamuel FID suer BY y ATTORNEY.

Patented Sept. 21, 1937 SIGNAL LAMP UNIT Samuel M. Doven Chicago, Ill.

Application March 7, 1936, Serial No. 67,693

y 8 Claims.

This invention relates to signal lights, and more particularly to such lights as are mounted on the outside of automobile trucks, or the like, and is specially concerned with a multiple light unit which shallbesimple and economical of construction `and possess other advantages hereafter set forth. The present invention is an improvement on the light unit shown in my copending application which. issued asPatent No. 2,033,692 on March 10, 1936.

It is one of the objects of the present invention to provide a light unit of the above character which has an improved contact arrangement for making contact with an electric light bulb. The improved contact arrangement issuch that the bulb` rests on a resilient support which substantially alleviates the 'shock due to vibration of the automobile. This result 'is accomplished, in the particular embodiment of the invention here illustrated, by providing a cushion of live rubber, preferably sponged rubber, which acts as a support for the contact strip and which exerts a yielding pressure to maintain the contact strip in lrm and intimate engagement with the base contact of an electric bulb insert, into the socket.

It is a further object of the present invention to provide a light unit of the above character which shall be substantially fully enclosed, against the entrance of moisture, dirt, or the like. f

It is a still further object of the present invention to provide a light unit of the above character which shall be of a minimum overall thickness.

The attainment of the above and further ob.- jects of the present invention will be apparent from the following specification taken in conjunction with the accompanying drawing forming a part thereof. f

In the drawing: y

Figure 1 is a side' View of a lighting unit constructed in accordance with the present invention, certain of the parts being broken away to illustrate the construction;

Figure 2 is a fragmentary longitudinal sectional view of the Contact strip and its supporting insulating strip;

Figure 3 is an end view of the unit;

Figure 4 is a fragmentary view of the under side of the web ofthe channel frame of the lighting unit at one of the light bulb sockets; and

Figure 5 is a transverse sectional view of the unit, said. view being taken through the` center of one of the lights.

In Figure 1 I have shown, by Way of illustration, a multiple light unit having three lights thereon. The unit comprises a sheet metal channel-shaped frame I within which, and on which, .the various parts are assembled. The anges of the channel are formed with additional anges 2-2 for mounting the unit in place, although it is to be understood that other mounting means may be used, if desired. Three holes, forming light bulb sockets, are formed in the Webf 3 of the channel, one of the holes being indicated at 4. At each of these sockets is secured a disc-like, shallow, substantially flat, lamp housing and cover lens holder 5, which is adapted to hold any preferred type of lens 6,-,in the usual manner. The lens holders 5 are each provided with an opening opposite the holes 4 of the channel-shaped frame, through which openings the metal of the web of the channel is projected to form a short cylindrical projection l. 4The cover lens'holders 5 are secured to the web of the channel in any desired manner, as by spot welding. The cylindrical formed portion 'l of the Web of the channel is of a diameter suicient to permit the stem of aproper-electric bulb to be inserted therethrough. The basel of-such a bulb has two diametrically opposite pins 8 projecting therefrom for holding the bulb in a bayonet type socket. To permit the bulb base, with its projecting pins, to pass through the cylindrical portion l, that portion is provided with two diametrically' opposite slots 9-9 through which the pins 8 pass. After the base of the bulb is inserted into the socket, the bulb is turned whereupon the pins 8 8 in the bulb base come opposite a pair of diametrically spaced short indentations lll-lil stamped on the inner side of the web of the channel at the edge of the opening 4, for holding the light bulb against turning.

The terminal assembly of the present invention comprises a rectangular strip i5 of 4suitable insulating material." This strip is comparatively strong and flexible. 'One suitable material is the substance known as Formica, which comprises thin sheets of paper impregnated with the substance known as bakelite, and treated by heat and pressure to form one unitary piece. Any other type of insulating material may be used. The narrow contact strip i6 extends along the strip l5 throughout substantially its entire length, and is passed through 'a pair of slots lli-ll to the upper side of the strip l5 at each point on the strip l5 that is opposite a bulb socket. The contact strip may be made of brass or any other metal of highelectrical conductivity. At one end of the strip I5, the end of the contact strip is folded over, as indicated at I8, to prevent accidental withdrawal of the contact strip from the insulating strip I5. At its opposite end the contact strip has an insulated electric conductor 20 secured thereto in contact making relationship, in any desired manner, as. for instance, by a rivet.

The terminal assembly comprises the strips I5 and I6, and rests on a spring support comprising a piece of resilient material 26 in a channelshaped enclosure frame 25. The insulating material 25 comprises, preferably, a strip of sponged rubber of a length and width such as to cause it to iit snugly within the channel 25. The sponged rubber strip 2'6 supports thestrip I5 throughout the full length of the strip I5,l and keeps the contact strip I out of engagement with the web of the channel 25. Itis thus apparent that the contact strip I6, together :with its insulating support I5, rests on a cushion of live rubber. The sponged rubber is comparatively soft so that it can yield considerably under pressure, such as may be exerted thereagainst by the tip of an electric light bulb of the type here involved. If desired, the material I'l" between two slots Il may be entirely removed, to make one big hole in the strip I5 opposite each socket 4, so that the base of the bulb may engage the strip I6 through the hole in the strip I5.

The flanges of the channel 25 fit snugly within the flanges of the channel I. The channels may, if desired, be welded together, although this is not necessary, The ends of the web of the channel I are bent downwardly as indicated at 2|, and constitute end closures for the unit. The two channels thus produce a long, narrow, rectangular housing which is substantially waterproo-f. When the terminal unit is inserted in place, and before the bulbs are inserted in their sockets, the terminal assembly lies substantially flat on the sponge rubber support and close to the web 3 of the channel I. When a bulb is inserted into its socket the tip contact in the base of the bulb engages the corresponding part of the contact strip I6 and forces the terminal assembly downwardly thus flexing the strips I5 and I6 downwardly. The sponge rubber 26 presses the terminal strip I6 against the contact at the lower end of the bulb base, thus maintaining a firm electric engagement with the bulb contact. Also, the spring pressure between the contact strip and the contact at the lower end of the bulb base prevents any rattling or turning of the bulb', thus preventing any loose electrical connections with the bulb. This rm electrical contact is maintained even though the vehicle on which the unit is mounted is subjected to considerable vibration.

It is to be noted that the members 5 lie substantially flat against the web 3 of the channel I. Thus there is little likelihood that ropes, or the like, may be caught between a disc-shaped member 5 and the web of the channel, with a resulting loosening of the disc member 5. It is also to be noted that an appreciable portion of the base of the bulb extends on the inner side of the channel I, thus reducing the overall height of the unit.

The circuit for each bulb is by way of the conductor 20, contact strip I6, the tip contact of the bulb, through the filament, and the base of the light bulb which is grounded through the grounded frame I.

In compliance with the requirements of the patent statutes I have here shown. and. described a preferred embodiment of my invention. It is, however, to be understood that the invention is not limited to the precise construction here shown, the same being merely illustrative of the principles of the invention. What I consider new and desire to secure by Letters Patent is:

l. A multiple light unit comprising a channelshaped frame having a plurality of electric bulb sockets formed in the web thereof, and within the trough of the channel a terminal assembly comprising a comparatively long and narrow strip of flexible insulation, a contact strip extending longitudinally of the insulating strip,

said contact strip being opposite the respective lamp sockets, and means for supporting the terminal assembly in the trough of the channel comprising a strip of rubber underlying the contact strip throughout the length thereof and providing a yielding cushion therefor.

2. A multiple light unit comprising a channelshaped frame having a plurality of electric bulb sockets formed in the webthereof, and within the trough of the channel a terminal assembly comprising a comparatively long and narrow strip of ilexible insulation, a contact strip extending longitudinally of the insulating strip, said contact strip being opposite the respective lamp sockets, and means for supporting the terminal assembly in the trough of the channel comprising a strip of rubber underlying the contact strip throughout the length thereof and providing a yielding cushion therefor, said contact strip being located between the flexible insulating strip and the rubber strip for a substantial portion of the length of the contact strip, and said contact strip and insulating strip being arranged to expose the contact strip opposite the respective sockets.

3. A terminal assembly comprising a comparatively long and narrow strip of flexible insulation, a contact strip extending longitudinally of the insulating strip along a surface of the insulating strip, said contact strip being laced through the insulating strip to the opposite surface thereof for a short portion of the length of the contact strip at a plurality of places intermediate its ends.

4. A light unit comprising a channel shaped frame having a hole in the web of the channel, lens receiving means comprising a substantially flat disc-shaped member lying flat on the web of the channel and secured thereto, said lens receiving means having a hole therein, an electric light-bulb having a stem extending through both holes, lcontact making means in the channel for establishing contact with the bulb, and means at the periphery of the lens receiving means for holding a lens, said last named means including a narrow rim of a width not exceeding the,

vamount that the stem of the bulb extends forward of the dat disc.

5. A light unit comprising a channel shaped frame member having a hole in the web of the channel, a substantially flat disc-shaped lens receiving member lying flat on the web of the channel and secured thereto, said lens receiving member having a hole therein, one of said members having a cylindrical projecting portion around the periphery of the hole therein, which projecting portion constitutes guiding means for an electric light bulb, and means at the periphery of the lens receiving member for holding a lens.

6. A multiple signal light unit adapted to be mounted on the outside of a vehicle, said unit comprising a comparatively long and narrow channel-shaped frame having spaced holes therein, electric bulbs at the respective holes with the bases of the bulbs extending through the holes into the trough of the channel, means entirely Within the trough of the channel exerting pressure against the bulbs for holding the bulbs against turning due to vibration and for establishing circuit connections thereto, said means including a 'contact making member and supporting means for said member Within the trough of the channel, said contact-making member engaging the contacts on the base of the bulbs, said supporting means being compressible and being compressed transversely of its length out of normal position by the tips of the bulbs, whereby said strip exerts a spring pressure on said bulbs, .and a closure for said channel, said supporting means resting on said closure.

7. A multiple light unit comprising a channelshaped frame having holes formed in a portion thereof for receiving electric light bulbs, a exible terminal assembly on the inner side of said portion and comprising a Contact strip extending lengthwise of the channel, in alignment with the holes and spaced from said portion to permit engagement of the contact strip by a bulb inserted in any of the holes, and means for supporting the terminal assembly comprising a strip of sponged rubber extending the full length of the contact strip, and means for supporting the sponge rubber strip.

8. A light unit comprising a comparatively long and narrow channel shaped frame member, a plurality of disc-shaped lens-receiving members supported on the outside of the Web of the channel in close relation thereto, a light bulb at each of the members and each bulb having a stem extending through the lens-receiving member into the trough of the channel, contact making means extending within the 'channel and engaging the respective bulb stems, and means at the periphery of each lens-receiving member for holding a lens, said lens holding means extending a distance from the web of the channel which is less than the length of a bulb stem.

SAMUEL M. DOVER. 

